1. The Field of the Invention
This invention relates to trailer drive apparatuses and more particularly to that class of device which is removably coupled to the trailer utilizing a single wheel drive without providing a riding seat for the operator of the device.
2. Description of the Prior Art
The prior art abounds with trailer drive arrangement for utility vehicles useful as a motor drive for trailers. U.S. Pat. No. 3,861,482 issued on Jan. 21, 1975 to W. J. Stephens et al. teaches a motor-driven wheel that is coupled through a rigid support to the front end of a trailer for moving the latter around when the wheel is in driving engagement with the ground. The ground wheel may be raised to an inoperative position off the ground, when desired. One or more springs act between the support and the ground wheel. The ground wheel may be turned to various angular positions with respect to the trailer.
U.S. Pat. No. 3,770,070 issued on Nov. 6, 1973 to J. B. Smith discloses a utility vehicle and vehicle mover that is power propelled, and may be moved by an individual to both lift and transport extremely heavy vehicles, such as trailers, when the vehicle has been disconnected from its prime mover. In one embodiment, the mover includes an adjustable power lifting means that may extend a distance under the trailer tongue for increased stability. In another embodiment, the mover mechanism is integral with the trailer tongue itself.
U.S. Pat. No. 3,861,483 issued on Jan. 21, 1975 to C. C. Pavelka discloses a tractor that has a mobile frame section carrying a hitch for connection with a mobile home or the like and a front section capable of being fully swivelled about its axis. Arching upwardly and forwardly from the mobile frame is a neck that is rigidly connected to a vertically disposed barrel which rotatably mounts a drum associated with the tractor front section. A columnar chassis extends from split axles and entirely through the drum so an upper part can support a motor and pivotally mount a steering mechanism. A differential gear assembly interconnects the split axles that extend from a pair of drive wheels. The steering mechanism is a U-shaped swing bar that can be maneuvered through a broad arc to clear the motor and other components while being swung from one side of the tractor to the other. During turning maneuvers by the tractor the differential gear assembly minimizes skidding and jerkiness tendencies.
All of the prior art suffer the common deficiency of providing a complex apparatus difficult to install to a trailer that is either multi-wheeled or manually operated and generally incapable for operating conveniently at angular locations including 360.degree. so as to facilitate backing-up of the trailer when desired.